Digital map display zooming method, digital map display zooming device, and storage medium for storing digital map display zooming program

ABSTRACT

A digital map display zooming method for continuously enlarging and reducing a displayed portion of a digital map as map information in digital form within a display screen is provided which comprises the steps of displaying the displayed portion of the digital map at the display screen, displaying a scroll part within the display screen for shifting the displayed portion, making the scroll part function as a scale setting part for carrying out enlarging and reducing operations of the displayed portion of the digital map within the display screen, and carrying out enlarging and reducing operations of the displayed portion of the digital map within the display screen by shifting a shifting operation part of the scale setting part.

BACKGROUND OF THE INVENTION

The present invention relates to a digital map display zooming method, adigital map display zooming device and a storage medium for storing adigital map display zooming program, which are for enlarging andreducing a displayed portion of a digital map as map information indigital form within a display screen.

Digital maps as map information in digital form are maps put intoelectronic form so as to be handled on the display screen of a computersuch as a portable computer etc. This kind of digital map is referred toas an electronic map or map software, where maps can be displayed on adisplay screen.

With this kind of digital map, a map is displayed on, for example, thedisplay screen of a portable computer so that an operation such that atarget is set on the map can be carried out, with these digital mapsbeing applied to car navigation systems etc. in recent years.

Incidentally, related art operation for enlarging or reducing thedisplayed portion of the digital map within the display screen iscarried out by a user operating prescribed buttons.

However, with this kind of operation for enlarging or reducing thedisplayed portion of the digital map, the displayed portion of thedigital map can only be enlarged or reduced in an intermittent manner oncertain scales of, for example, about four steps. The displayed portionof the digital map therefore cannot be displayed at a scale on which theuser wishes to set.

It is therefore an object of the present invention to solve theaforementioned problem to provide a digital map display zooming method,a digital map display zooming device and a storage medium for storing adigital map display zooming program which are capable of easilydisplaying the displayed portion at an arbitrary rate of enlargement bya user continuously enlarging or reducing the displayed portion of thedigital map while watching the display screen.

SUMMARY OF THE INVENTION

The above object can be achieved in the present invention by a digitalmap display zooming method for enlarging and reducing a displayedportion of a digital map as map information in digital form within adisplay screen, the method comprising the steps of displaying thedisplayed portion of the digital map at the display screen, displaying ascroll part within the display screen for shifting the displayedportion, making the scroll part function as a scale setting part forcarrying out enlarging and reducing operations of the displayed portionof the digital map within the display screen, and carrying out enlargingand reducing operations of the displayed portion of the digital mapwithin the display screen by shifting a shifting operation part of thescale setting part.

In the present invention, the scroll part displayed within the displayscreen for shifting the displayed portion functions as a scale settingpart for carrying out enlarging and reducing operations of the displayedportion of the digital map. The user can then carry out enlarging andreducing operations of the displayed portion of the digital map withinthe display screen by shifting the shifting operation part of the scalesetting part.

In this way, the user can freely carry out enlarging and reducingoperations of the size of the displayed portion displayed at the displayscreen with ease by only shifting the shifting operation part of thescale setting part within the display screen while watching the shiftingoperation part of the scale setting part of the display screen.

In the present invention, if the user preferably carries out anoperation while looking at the side end of the display screen so thatthe displayed portion of the digital map is continuously reduced whenshifting the shifting operation part of the scale setting part in anupward direction of the display screen, and on the contrary, thedisplayed portion of the digital map is continuously enlarged whenshifting the shifting operation part of the scale setting part in adownward direction of the display screen, there will be no mistakes inthe zooming operations because the displayed portion of the digital mapwill be enlarged and reduced in conformity with the sense of up and downof the user.

The above object can also be achieved in the present invention by adigital map display zooming device for enlarging and reducing adisplayed portion of a digital map as map information in digital formwithin a display screen, the device comprising a display section havinga display screen for displaying the displayed portion of the digitalmap, a scale setting part provided to be displayed at the display screenof the display section, the scale setting part comprising a scroll parthaving a shifting operation part and being displayed at the displayscreen with a function thereof being changed for shifting the displayedportion, and carrying out enlarging and reducing operations of thedisplayed portion of the digital map within the display screen byoperating the shifting operation part, a pointing device for operatingthe shifting operation part of the scale setting part, and an arithmeticprocessor for carrying out processing for enlarging and reducingoperations of the displayed portion of the digital map within thedisplay screen by shifting the shifting operation part of the scalesetting part with the pointing device being operated.

In the present invention the displayed portion of the digital map isdisplayed at the display screen of the display section. The scalesetting part is displayed at the display screen. This scale setting partis a scroll part displayed at the display screen with a function thereofbeing changed for shifting the displayed portion. The operation ofzooming the displayed portion can then be carried out by operating theshifting operation part.

The pointing device is for the user to operate the shifting operationpart of the scale setting part.

The arithmetic processor carries out processing for carrying outenlarging and reducing operations of the displayed portion of thedigital map within the display screen by shifting the shifting operationpart of the scale setting part by operations of the pointing means.

As a result, the user can freely carry out enlarging or reducingoperation with ease for the size of the shifting displayed portiondisplayed at the display screen only by shifting the shifting operationpart of the scale setting part within the display screen while watchingthe shifting operation part.

The aforementioned object can also be achieved in the present inventionby a storage medium for storing a digital map display zooming programfor enlarging and reducing a displayed portion of a digital map as mapinformation in digital form within a display screen, wherein the programcomprises the steps of displaying the displayed portion of the digitalmap is displayed at the display screen, displaying a scroll part withinthe display screen for shifting the displayed portion, making the scrollpart function as a scale setting part for carrying out enlarging andreducing operations of the displayed portion of the digital map withinthe display screen by operating the pointing means, and carrying outenlarging and reducing operations of the displayed portion of thedigital map within the display screen by shifting a shifting operationpart of the scale setting part.

In the present invention, the user can freely carry out enlarging orreducing operation with ease for the size of the displayed portiondisplayed at the display screen only by shifting the shifting operationpart of the scale setting part within the display screen while watchingthe shifting operation part.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing a portable notebook-type personalcomputer as an embodiment of a digital map zooming device of the presentinvention;

FIG. 2 is a block diagram showing a system for the digital map zoomingdevice of FIG. 1;

FIG. 3 is a view showing an example of a displayed portion of a digitalmap displayed on the display screen of the digital map display zoomingdevice of FIG. 1;

FIG. 4 is a view showing an example of an enlarged display of thedisplayed portion of the digital map of FIG.

FIG. 5 is a view showing a scale bar, a scale bar knob and a mouse;

FIG. 6 is a perspective view showing another example of a mouse as apointing means used in the present invention;

FIG. 7 is a side view of the mouse of FIG. 6;

FIG. 8 is a view showing a flowchart for processing as a scale bar knob;

FIG. 9 is a view showing a flowchart of a scale bar display;

FIG. 10 is a view showing a concept of continuous enlargement andreduction as continuous zooming; and

FIG. 11 is a view showing a flowchart of continuous zooming.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following a preferred embodiment of the present invention will bedescribed in detail on the basis of the attached drawings.

The embodiment described in the following is a specific preferredexample of the present invention and is thereby subject to varioustechnical limitations. However, the scope of the present invention is byno means limited to these forms in the following explanation unlessotherwise described to limit the present invention.

FIG. 1 is a perspective view showing a preferred embodiment of a digitalmap zooming device 100 of the present invention. A system configurationfor this digital map zooming device 100 is shown in FIG. 2.

The digital map zooming device 100 of FIG. 1 is a so-called portablenotebook type personal computer which has a main body 2, display means3, a mouse 6, a touch pad 12 and touch pads 31 and 32. The display means3 has a display screen 4 to which, for example, a Liquid Crystal Display(LCD) can be adopted. The display means 3 is attached to the main body 2in such a manner as to be capable of being opened and closed.

The main body 2 has the aforementioned mouse 6, touch pads 12, 31 and 32and a keyboard 11 as pointing means, and a power supply lamp 15 etc.

FIG. 2 is a block diagram showing the system configuration within themain body 2 and the display means 3.

The main body 2 has a floppy disc drive (FDD) 86, a CD-ROM (read-onlymemory utilizing a compact disc) drive 87, a detector circuit 84 for akeyboard 11, a CPU (central processing unit) 81, a ROM (read-onlymemory) 82, a RAM (random access memory) 83 and a controller 51.

Touch pads 12, 31, 32 and a mouse 6 are connected to a controller 51.The controller 51, the ROM 82, the RAM 83, the detector circuit 84, thehard disc drive 85, the floppy disc drive 86 and the CD-ROM drive 87 areconnected to a CPU 81 via a bus BA.

The mouse 6 of FIG. 1 has a mouse body 6 a, a left button 6 b and aright button 6 c. The touch pad 31 with a function similar to that ofthe left button and the touch pad 32 with a function similar to that ofthe right button are provided below the touch pad 12.

The CPU 81 of FIG. 2 executes various processings in accordance with aprogram stored at the ROM 82. The data and programs etc. necessary forthe CPU 81 to execute various processes are stored in an appropriatemanner at the RAM 83. The detector circuit 84 detects operation of thekey 11 and outputs a detection signal to the CPU 81.

The hard disc drive (HDD) 85 stores programs processed by the CPU 81 anddata etc. in an appropriate manner. The floppy disc drive (FD) 86records and plays back data to and from a floppy disc 89 installedtherein.

The controller 51 detects operations of the touch pad 12, the touch pads31 and 32 and the mouse 6 and outputs a detection signal to the CPU 81.

When the user shifts a pointer 5 using the touch pads 12, 31 and 32, theuser touches (presses) a prescribed position on the touch pad 12 withtheir finger, and shifts this touching position in the direction thatthe pointer 5 is to be shifted. The controller 51 detects thisoperation, i.e. when the user applies a pressure to the touch pad 12with their finger, the electrostatic capacity of the position beingpressed changes. For example, when a certain position on the touch pad12 is pressed by a finger, the electrostatic capacitance between ahorizontal electrode and a vertical electrode changes largely comparedto the electrostatic capacitance between other electrodes.

When a key of the keyboard 11 is operated, the detector circuit 84outputs a detection signal corresponding to this operation to the CPU81. The CPU 81 then generates, for example, prescribed character data inaccordance with this inputted detection signal with this character databeing outputted to the display screen 4 and displayed. In a similarmanner, the CPU 81 reads out graphics data for the pointer 5 stored inthe ROM 82 and outputs this data to the display screen 4 for displaying.In this way, the pointer 5 is displayed as shown, for example, in FIG.1.

The controller 51, CPU 81, ROM 82, RAM 83 and detector circuit 84 inFIG. 2 comprise arithmetic processing means 120. The arithmeticprocessing means 120 is a portion having a function for carrying outenlarging and reducing operations of the displayed portion of a digitalmap within the display screen as a result of shifting a shiftingoperation part of a scale setting part to be described later byoperating the mouse 6 as the pointing means.

FIG. 3 shows an image 130 included in a digital map display zoomingprogram displayed on the display screen 4 of the display means 3 of FIG.1 and FIG. 2. Although this image 130 is simply an example, a title bar131, a menu bar 132, a tool bar 133, a (information display) list box134, a guidance area 135, a map display region 136, a map window titlebar 138, a scale display 139, a latitude/longitude display 140, a (zoomin) button 141, a (zoom out) button 142, a scale bar 143, a scale barknob (also referred to as “slider”) 144, a maximizing button 145, aminimizing button 146 and an X button (close button) 147 etc. aredisplayed within this image 130. A separate window 130 b is displayedwithin a window 130 a of the image 130.

An example of a displayed portion 150 of the digital map is displayedwithin this window 130 b of FIG. 3 and FIG. 4 that is an enlargeddisplay of the displayed portion 150 of FIG. 3. The menu bar 132 ispositioned below the title bar 131 and is lined up with function names,and when clicking is performed with the pointer 5 being positioned atthis menu bar 132, a more detailed display is given. A window is adisplayed portion surrounded by a window-like frame opened on thecomputer screen. The term “clicking” means an operation of quicklypressing and releasing the mouse button.

FIG. 5 shows a scale bar 143 as the scale setting part shown in FIG. 3and FIG. 4 and a scale bar knob 144 as a shifting operation part of thescale setting part together with the mouse 6. The scale bar knob 144 andthe scale bar 143 can also be selected to function as a scroll bar forscrolling pictures.

The scale bar knob 144 is pointed out by an arrow-type pointer 5 bypressing the left button 6 b of the mouse 6 as the pointing means ofFIG. 1 and this scale bar knob 144 can be shifted in a reducingdirection DR1 (upwards on the display screen) as a result of the usermoving the mouse 6 in a direction of, for example, E1 on a desk DK. Thescale bar knob 144 can then be shifted in an enlarging direction DR2(downwards on the display screen 4) as a result of the user moving themouse 6 in a direction E2.

When the scale bar knob 144 is shifted in the reducing direction DR1,the displayed portion of the digital map 150 displayed at the displayscreen 4 shown in FIG. 3 and FIG. 4 can be continuously (in an analogmanner) reduced in accordance with the amount of shift. For example, thedisplayed portion of the digital map 150 is continuously reduced as thescale bar knob 144 goes along marks M1, M2, M3, M4 and M5 of the scalebar 143. This presents an image seen from a manned spacecraft risingfrom earth into space.

Contrary to this, when the scale bar knob 144 is shifted in theenlarging direction DR2, the displayed portion of the digital map 150can be continuously (in an analog manner) enlarged. This gives an imageseen from a spacecraft descending from space to the surface of theearth.

When clicking is made with an arbitrary position of the scale bar 143being pointed out by the pointer 5, the displayed portion 150 for themap is displayed on the scale value for this position.

In the embodiment in FIG. 5, the marks M1, M2, M3, M4 and M5 of thescale bar 143 show changeover positions i.e. dividing positions of dataof the digital map which are also referred to as map layers. Theenlargement rate is kept to be changed markedly at each of the marks M1to M5 as the scale bar knob 144 is shifted along the marks. Theenlargement rate of the displayed portion of the digital map 150 can bethen made to be changed, for example, in accordance with the enlargementrate indicated by characters at the marks M1 to M5.

FIG. 6 shows another example of a mouse which is different from themouse 6 of FIG. 1 and FIG. 5. This mouse 106 is in the tradename“Intellimouse” of the Microsoft Co., Ltd. with a left button 106 b,right button 106 c and rotary wheel 106 d provided at a main body 106 a.

For example, by the user rotating the rotary wheel 106 d in thedirection R1 while holding down the left button 106 d of the mouse 106,the scale bar knob 144 of FIG. 5 can be shifted in the reducingdirection DR1 by the amount of rotation of the rotary wheel 106 d.Moreover, by rotating the rotary wheel 106 d in the direction R2, thescale bar knob 144 can then be shifted in the enlarging direction DR2 inaccordance with the amount of rotation.

A mouse is a device that is slid on a desk to point specific portions ofthe screen.

The programs for the digital map display zooming method in theembodiment of the present invention are shown in FIG. 8, FIG. 9 and FIG.11. The programs are operated on the operation system such as Windows'95 of the Microsoft Co., Ltd. in U.S. The operating system (OS) is asoftware with functions such as “execution of applications” and “filemanagement” that are the basis for using a computer.

The program for the display zooming method is stored on, for example,the CD-ROM 88 of FIG. 2. The digital map display zooming program of thisCD-ROM 88 can then be put onto the hard disc drive 85 by inserting theCD-ROM 88 into the CD-ROM drive 87.

Alternatively, such a digital map display zooming program can be storedon the floppy disc 89 instead of the CD-ROM 88. When the floppy disc 89is inserted into the floppy disc drive 86, the digital map displayzooming program within this floppy disc 89 is then put onto the harddisc 85.

Alternatively, the digital map display zooming program can be put ontothe hard disc drive 85 from outside via a network such as the internet.

FIG. 8 shows an example of the processing for enlarging operation of thedisplayed portion 150 at the display screen 4 when the scale bar knob(also referred to as a slider) 144 shown in FIG. 5 is shifted by theuser. In step SP50, an event occurs when the user shifts the scale barknob 144. In step SP51, the current position of the knob i.e. the lengthfor the current position of the scale bar knob 144 (LENGTH_(KNOB)) atthe scale bar 143 is obtained.

In step SP52, a map layer A with a length of LENGTH A is obtained whichis the minimum of the lengths of LENGTH N for the map layers N at thedisplayed portion of the digital map 150 that satisfy the conditionLENGTH N≧LENGTH_(KNOB). In step SP53, the enlargement rate is thenobtained and in step SP54 the map layer A of the displayed portion isdrawn at the obtained enlargement rate. The map layer is referred to asmap data of the digital map.

FIG. 9 shows an example of the processing for displaying each of scalesfor map data (layers) of a plurality of scales stored on a map disc(storage medium) such as the CD-ROM 89 on the scale bar 143.

When a CREATE/RESIZE event for a map window is received in step SP100 ofFIG. 10, the length of the scale bar 143 at the display screen(LENGTH_(S)) is obtained in step SP101. In step SP102, scale information(unit: Meter/Dot) for all of the map layers on the map disc is read out.

In step SP103, the scale of the map layer for the broadest region of thepresented ones is taken to be Smax and the scale Smin of the map layerfor the narrowest region is determined to be Smin=0.5 Meters/Dot.

In SP104 and SP105, conversion coefficients K are calculated and thepositions N of various map layers L are calculated. In step SP106,linear markers M1 to M5 as shown in FIG. 5 are displayed at prescribedpositions of the scale bar 143 for various layers N.

FIG. 10 conceptually shows a currently selected digital map layer ofscale Sn used in a continuous zooming, namely continuous enlargement andreduction, of the displayed portion, a digital map layer of scale S(n−1)for one-step enlargement and a digital map layer of scale S(n+1) forone-step reduction in three dimensions.

The above digital map layers are the data for the program shown by theflowchart of FIG. 11.

Next, an example of carrying out a zooming operation of the displayedportion 150 of the digital map in FIG. 3 in accordance with the digitalmap zooming display program will be described with reference to FIG. 11.

A CD-ROM 88 is inserted into, for example, the CD-ROM drive 87 of FIG.2. Alternatively, a floppy disc 89 is inserted into the floppy discdrive 86.

As a result, a preferred embodiment of the digital map display zoomingprogram of the present invention, which is stored on the CD-ROM 88 orthe floppy disc drive 89, is put onto the hard disc drive 2 of the harddisc via the bus BA.

When these preparations are finished, the window 130 b is displayed atthe display screen 4 of the display means 3 of FIG. 3. This window 130 bis a window of the digital map.

FIG. 11 is a flowchart showing continuous zooming at the displayedportion 150 of the digital map. At the time of starting continuouszooming using the scale bar knob 144 of FIG. 5, the scale for the maplayer, i.e. data, within the storage disc such as the CD-ROM is taken tobe Sn (unit: meter/dot) and this data is supposed to be in beingdisplayed at the display screen 4 of FIG. 1 on a scale Sc.

Further, the unit (meter/dot) for the scale S expresses the actualdistance on the map corresponding to one display pixel.

In FIG. 11, fzoom-in (Sc) represents the enlargement rate (for example,80%) and fzoom-out (Sc) represents the reduction rate (for example,125%). The enlargement rate and the reduction rate both relate to twodimensions (line segments).

Currently, the enlargement rate and the reduction rate are set so thatthey are in a relation as fzoom-in=(1/fzoom-out)=constant (for example,0.8), but this value can be freely changed if so desired. For example,an operation is also possible which increases the enlargement ratedepending on acceleration as the surface of the earth 2 becomes closer.

Upon starting in step SP1 of FIG. 11, it is assumed that the displayedportion of the digital map has already been in the zoom mode at thisstart time.

In step SP2 a determination is made as to whether or not the scale barknob 144 of FIG. 5 has been shifted in the reducing direction DR1(upwards) or the enlarging direction DR2 (downwards).

When the scale bar knob 144 is shifted downwards, the process goes toenlargement processing of step SP3, and when the scale bar knob 144 isshifted upwards, the process goes to the reduction processing of stepSP10.

In step SP3, a calculation is carried out for the next scale “New Scale”that is to be set by the user with the scale bar knob 144. This newscale is expressed as “Snew”. In step SP4, a scale S(n−1) for a maplayer (data) is obtained which is for one-step enlargement of thedigital map currently being displayed.

In step SP5, the new scale Snew and the scale S(n−1) in step SP4 arecompared. When the new scale Snew is greater, the process goes to stepSP6, and when this is not the case, the process goes to step SP7.

In step SP6, the map layer (data) currently being displayed is enlargedand displayed. While, in step SP7, the map layer (data) for one-stepenlargement is enlarged.

By doing this, the displayed portion can be displayed with respect tothe object data at the display screen 4 in FIG. 5.

Compared with this, in step SP10, a calculation is carried out for thenext scale “New Scale” that is to be set by the user with the scale barknob 144. When this new scale “Snew” is larger than the scale S(n+1) ofthe map layer on the disc, the process goes to step SP12 and when thisis not the case the process goes to step SP14.

In step SP12, a scale S(n+1) for the map layer is obtained which is forone-step reduction of the map currently being displayed. Then, in stepSP13, the map layer (data) is reduced which is for one-step reduction.Compared with this, the map layer (data) currently being displayed isthen reduced in step SP14.

The object data can thus be displayed in being enlarged or reducedcontinuously and smoothly in response to the scale bar knob 144 beingshifted by the user.

The present invention is by no means limited to the above embodiment.

In the above embodiment an example is shown where the digital mapdisplay zooming program of the present invention is stored on the CD-ROM88 or the floppy disc drive 89 shown in FIG. 1. However, the presentinvention is by no means limited in this respect, and this can also bestored so as to be installed beforehand on a hard disc of the hard discdrive 85. Alternatively, this digital map display zooming program can bestored on, for example, the hard disc 85 of the hard disc drive via anetwork such as an external internet. Other types of disc such as ahigh-density recording disc (DVD) can also be used as the recordingmedium.

Further, the digital map display zooming device of FIG. 1 is a notebooktype personal computer, but the present invention is by no means limitedin this respect, and can also be applied to desktop personal computers,navigation systems mounted on moving vehicles such as cars and toportable navigation systems.

As described above, according to the present invention, the displayedportion can easily be displayed at an arbitrary enlargement rate by theuser continuously enlarging or reducing the displayed portion of thedigital map while watching the display screen.

1. An apparatus for enlarging and reducing a displayed portion of animage, comprising: a memory means for storing a plurality of image datalayers having different scale ratios, each of the plurality of imagedata layers corresponding to a single map; a display means fordisplaying a portion of the map; an input means for accepting anarbitrary amount of a user's operation; a scale setting means foridentifying a desired degree of scale reduction/enlargement of saidportion of the map based on said accepted arbitrary amount of the user'soperation; and an arithmetic processing means for retrieving one of theimage data layers from memory based upon the setting of the scalesetting means to provide a corresponding enlargement or reduction inscale of the portion of the map displayed, by providing the retrievedimage data layer to the display means.
 2. The apparatus according toclaim 1, wherein a relationship between said scale ratio set by saidsetting scale means and said accepted arbitrary amount of the user'soperation accepted by said input means is non-linear.
 3. The means forenlarging and reducing a displayed portion of an image according toclaim 1, wherein a relationship between said means of setting and saidaccepted arbitrary amounts of the user's operation accepted by saidmeans for accepting is non-linear.
 4. A digital map display zoomingmethod for enlarging and reducing a displayed portion of an imagecomprising the steps of: storing a plurality of image data layers havingdifferent scale ratios, each of the plurality of image data layerscorresponding to a single map; displaying a portion of the map;accepting an arbitrary amount of user's operation; identifying a desireddegree of scale reduction/enlargement of said portion of the map basedon said accepted arbitrary amount of the user's operation; andretrieving one of the image data layers from memory based upon theidentification to provide a corresponding enlargement or reduction inscale of the portion of the map displayed, by providing the retrievedimage data layer to a display.
 5. A computer program product including acomputer readable medium, for enlarging and reducing a displayed portionof an image, said computer program product comprising: a memory accessmechanism configured to store a plurality of image data layers havingdifferent scale ratios, each of the plurality of image data layerscorresponding to a single map; a display mechanism means configured todisplay said portion of the map; an input mechanism configured to acceptan arbitrary amount of user's operation; a scale setting mechanismconfigured to identify a desired degree of scale reduction/enlargementof said displayed portion of the image data based on said acceptedarbitrary amount of the user's operation; and an arithmetic processingmechanism configured to retrieve one of the image data layers frommemory based upon the setting of the scale setting means to provide acorresponding enlargement or reduction in scale of the portion of themap displayed, by providing the retrieved image data layer to thedisplay means.